10 Mediterranean Diet Studies

Interest in the relationship between the Mediterranean region and the longevity of its denizens was sparked in middle of the 20th century when folks began to notice that people in southern Europe seemed to be living longer than people who lived in northern Europe and the United States. Since then, several studies have been conducted trying to find the reason. Here are ten of them.

The Seven Countries Study

Funded by a grant from the National Heart Institute and lead by Ancel Keys, this decades-long study was one of the first to examine the link between lifestyle and disease.

Specifically, the Seven Countries study followed population of men, ages 40 to 59, from seven countries, looking for association among diet, known risk factors, and the prevalence of heart attacks and stroke.

The study’s major findings include the observation that the risk of heart attack and stroke is directly related to the level of total serum cholesterol, a finding that held true for all groups studied, and that having high cholesterol and being overweight or obese was associated with increased cancer deaths.

Although it didn’t specifically study the Mediterranean diet, researchers observed that southern Europe had far fewer coronary deaths than northern Europe and the United States did, even when factoring in other known risks like age, smoking, blood pressure, and physical activity.

The SUN Project

The SUN Project, from the University of Navarro, Spain, was an ongoing study that sought to identify dietary causes of various health conditions, such as high blood pressure, diabetes, obesity, and heart disease. This project produced some interesting findings:

Participants who followed a Mediterranean-style diet were less likely to develop type 2 diabetes.

Participants who ate a diet rich in olive oil had a reduced risk of hypertension (a finding that was statistically significant only among the men) and heart disease.

Those whose diets included trans-unsaturated fatty acids were at greater risk of depression, and the greater the consumption of healthy fats, the lower the risk for depression.

The PREDIMED trial

The PREDIMED (Prevención con Dieta Mediterránea) trial, conducted in Spain and launched in 2003 with results published in 2013, was designed to determine whether, and to what degree, a Mediterranean diet prevents cardiovascular disease.

It specifically compared a low-fat diet to a Mediterranean diet, supplemented with either extra-virgin olive oil or tree nuts, to see which was most effective at preventing heart disease, heart attacks, and strokes.

Evidence showed that a Mediterranean-based diet, whether supplemented with nuts or extra-virgin olive oil, reduced the risk of heart disease by a whopping 30 percent.

The EPIC project

The goal of the EPIC (European Prospective Investigation into Cancer) project was to explore the relationship between diet, lifestyle, and cancer, as well as other chronic diseases, like heart disease.

Bottom line: You can add years to your life by engaging in these key behaviors: being physically active, eating at least five servings of fruits and vegetables a day (the Mediterranean diet has you eating between seven and ten servings), moderating how much alcohol you drink, and not smoking.

Research from the University of Louisiana’s College of Pharmacology

A healthy brain has 100 billion nerve cells (neurons) that connect in an intricate web, called a neuron forest. Signals that form memories, ideas, and feelings travel from neuron to neuron in this forest. In a brain afflicted with Alzheimer’s, problems occur when the two key proteins stop functioning properly and result in plaques and tangles being formed.

At this point, the cells, deprived of nutrients, die.

In the study, researchers showed that oleocanthal, a compound in extra virgin olive oil, helps decrease the accumulation of beta-amyloid in the brain by enhancing the production of other proteins and enzymes thought to be critical in removing beta-amyloid. The implication was that following a Mediterranean diet that features extra virgin olive oil has the potential to reduce the risk of Alzheimer’s and other dementias.

The NIH-AARP diet and health study

Together the National Institutes of Health and AARP (formerly known as the American Association of Retired Persons) conducted a study that investigated the link between diet and health.

The NIH-AARP Diet and Health study published in the Archives of Internal Medicine in 2007 found that people who closely adhered to a Mediterranean-style diet were 12 to 20 percent less likely to die from cancer and all causes.

The ATTICA study

The ATTICA study, published in the September 2005 issue of the American Journal of Clinical Nutrition, measured the total antioxidant capacity of men and women in Greece. It found that the participants who followed a traditional Mediterranean diet had an 11 percent higher antioxidant capacity than those who didn’t adhere to a traditional diet.

The findings also showed that the participants who followed the traditional diet the most had 19 percent lower oxidized LDL (bad) cholesterol concentrations, which may potentially lower the risk of developing heart disease.

Harvard School of Public Health study

Beginning in 1976, researchers from the Harvard School of Public Health followed 88,000 healthy women and found that the risk of colon cancer was 2.5 times higher in women who ate beef, pork, or lamb daily compared with those who ate those meats once a month or less. They also found that the risk of getting colon cancer was directly correlated to the amount of meat eaten.

2008 study reviews regarding cancer risk

In addition to ingredient-specific studies, the diet as a whole has some promising research. A 2008 study review published in the British Medical Journal showed that following a traditional Mediterranean diet reduced the risk of dying from cancer by 9 percent.

That same year, the American Journal of Clinical Nutrition published a study that showed that, among post-menopausal women, those who followed a traditional Mediterranean diet were 22 percent less likely to develop breast cancer.

A study of 26,000 Greek people published in the British Journal of Cancer showed that using more olive oil cut cancer risk by 9 percent.

Study from Second University of Naples

A 2009 study from the Second University of Naples in Italy, published in the Annals of Internal Medicine, found that diabetics who followed a Mediterranean diet instead of a low-fat diet had better glycemic control and were less likely to need diabetes medication.